Heat and moisture exchange devices are often used to provide moisture to gases from a ventilator for respiratory therapy. To this end, a heat-moisture exchanger (HME) is positioned in the respiratory circuit, such a device containing a material or composition capable of absorbing heat/moisture from patient exhaled gas and desorbing the heat/moisture into the cool/dry respiratory gas stream from the ventilator for patient inhalation.
For treating some respiratory conditions, it is desirable to introduce an aerosol generated by a nebulizer to the gas delivered to a patient. When such treatment is provided, it is desirable to bypass the HME to avoid absorption of the aerosol in the HME material. To avoid the inconvenience and inefficiency of removing the HME device each time aerosol treatment is to be administered, HME bypass devices have been designed, such as described in U.S. Patent Application Publication No. 2004/0084046. However, operating the prior art device between HME and bypass functions requires rotation of the housing portions causing rotation of the pipes at each end of the housing portions. Such housing and pipe rotation is transferred to the attached patient circuit tubing resulting in disturbing or loosening the pipe connections and contributes to inadvertent tubing disconnects affecting patient ventilation or necessitates repositioning of the patient ventilator circuit to relieve the added torque along the tubing.